\global\long\def\x{\mathbf{x}}
\global\long\def\p{\mathbf{p}}
\global\long\def\z{\mathbf{z}}
\global\long\def\e{\mathbf{e}}
\global\long\def\y{\mathbf{y}}
\global\long\def\tu{\boldsymbol{\tau}}
\global\long\def\r{\mathbf{x}^{r}}
\global\long\def\b{b}
\global\long\def\s{\mathbf{x}^{i}}
\global\long\def\v{\mathbf{v}}
\global\long\def\a{\mathbf{a}}
\global\long\def\q{\mathbf{q}}
\global\long\def\B{\mathbf{B}}
\global\long\def\P{\mathbf{P}}
\global\long\def\R{\mathbb{R}}
\global\long\def\w{\boldsymbol{\omega}}%
\global\long\def\prange{\rho}
\global\long\def\PHI{\boldsymbol{\Phi}}
\global\long\def\skew#1{\left\lfloor #1\right\rfloor ^{\times}}%